Chemistry

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Boiling Point Calculator.

Invert an Antoine vapor-pressure correlation with coefficients and pressure units you provide.

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Boiling temperature: 100 °C

Boiling temperature

100.00°C
Pressure: 101.32 kPa

Pressure

101.32kPa

How to Use

T = B ÷ (A − log₁₀(Pnative)) − C. Enter coefficients from a named correlation and its pressure scale.

Use a named source for any material-specific coefficient. This page does not infer local rates, species tables, laboratory methods, or safety guidance.

Use Cases

Determine boiling point at reduced pressure

Useful in chemistry labs or industrial processes where you need to know the boiling point of a substance under vacuum or elevated pressure.

Example: Find the boiling point of water at 0.5 atm using known Antoine coefficients.

Verify Antoine coefficients

Check if a set of Antoine coefficients correctly predicts a known boiling point at a given pressure.

Example: Confirm that coefficients for ethanol give 78.3°C at 1 atm.

Frequently Asked Questions

How does the boiling point calculator work?
You provide Antoine coefficients A, B, and C, along with a target pressure. The calculator inverts the Antoine equation to solve for temperature, giving the boiling point at that pressure.
What units can I use for pressure?
You can enter the target pressure in any unit you choose, and also specify the conversion factor from that native pressure unit to kPa. The calculator uses this to convert to kPa internally.
What is the Antoine equation?
The Antoine equation relates vapor pressure to temperature: log10(P) = A - B/(C + T). Here, P is pressure, T is temperature, and A, B, C are substance-specific coefficients. This calculator solves for T given P.

Tips & Common Mistakes

Tips

  • Ensure your Antoine coefficients are for the same temperature scale (usually Celsius) and pressure unit (usually mmHg or kPa) as used in the equation.
  • The calculator expects pressure in kPa internally, so provide the correct conversion factor from your native unit to kPa.
  • Double-check that the target pressure is within the valid range for the Antoine coefficients you are using.
  • Use consistent units for temperature: if your coefficients are in Celsius, the result will be in Celsius.

Common Mistakes to Avoid

  • Using coefficients that are not for the same substance or temperature range, leading to inaccurate results.
  • Forgetting to convert pressure to kPa or entering the conversion factor incorrectly.
  • Misinterpreting the sign of the C coefficient; it is usually positive but can be negative for some substances.

Last updated: August 13, 2026